Evaluation of Photoacoustic Transduction Efficiency of Candle Soot Nanocomposite Transmitters

Candle soot nanoparticles (CSNP) and polydimethyl-siloxane (PDMS) composite has shown the highly efficient photoacoustic transduction owing to their high light absorption coefficient and low interfacial thermal resistance. In this study, we report the effect of candle soot structure and thickness on the photoacoustic transduction efficiency. Optical properties of the CSNP/PDMS nanocomposites were characterized through both experimental measurements and finite difference time domain analysis in the visible wavelength range, indicating that the carbon volume fraction and thickness of CS/PDMS composite are highly relevant with light absorption. With a low laser energy input ( $ ), the CS/PDMS composite with 2.15  μ m thickness exerts an output pressure of 3.78 MPa and a conversion efficiency of ${\text{9.69}}\,\times \,{\text{10}}^{- 3}$ , which is two orders of magnitude higher than previously reported results.